Carburetor



J. S. CUFF CARBURETOR May 5, 1931.

Filed Jan. 30, 1929 INVENTOR JLM/55 S. CUF/f ATTORNEYS Patented May 5,1931` UNITED STATES JAMES SYLVESTER UUFF, OF NEW LONDON, CON NEGTICU'1'Y CARBURETOR Application filed January 30, 1929. Serial No. 336,075.

` 1o tain substantially only liquid fuelfor priming the engine; toobtain the proper mixture ,i or gas for the engine when it is desired toallow it to idle; to obtain a fuel mixture of air and liquid fuel in theform of a gas, in a single operation;v and to cut olf the supply .ofliquid fuel while admitting air only to the engine in a singleoperation, so as to convertA the engine into an air compressor for thepurpose of holding the vehicle with an action similar to'that of abrake, while obviating a vacuum in the cylinders which ordinarily drawsin oil from the crank case resulting in carbon and waste oil in thecylinders, which is also obViated.

The nature of the invention and its4 distinguishing features andadvantages will appear when the following specification is read inVconnection with the accompanying drawings, in which- Figure 1 is anlelevation of a carburetor embodying the .present invention.

Fig. 2 is a sectional view taken on the line 2--2 of Fig. 1.

Fig. 3 is a transverse sectional View taken on the line 3-3 of Fig..1.

Referring now more particularly to .the

several views of the drawing, it will be ap-A parent that, thecarburetor Vin the present `instance will include a easing 10 formed toprovide a flange 11 by virtue' of which the carburetor is attached tothe intake of the usual manifold of an internal combustion engine, anair inlet 12, and a mixing chamber 13 in communication with the airinlet 12.

i A liquid fuel inlet 14 is arrangedwithin the mixing chamber 13. Theair inlet 12 is controlled by a choke valve 15 which is arran ed betweenthe inlet 12 and the 'mixing cham er 13. The choke valve 15 includes arotatable shaft 16. The liquid fuel inlet 14 is controlled by a valve,which in the present instance, includes a valve member 17 having theusual pointed end 18 which coacts with a tapered seat 19 to control theflow of liquid fuel through the passage 20 of the inlet 14. The saidinlet 14 will be connected :to the usual liquid fuel supply lioatchamber. The valve controlling the inlet 14 also includes a block or nut21 in threaded engagement with the threaded stemof the valve member 17,and a j amb nut 22 also threaded on said stem to aid in holding the nut21 in the desired adjustment. The valve member 17 is arranged in a bore23 of an extension 24 on the inlet 14. A sleeve`25 surrounds the stem ofthe valve member 17 and is arranged between the end portion of the nut21 and a spring 26 which also surrounds the stem and has one enclinengagement with a collar 27 while its 'opposite end lis in engagementwith the sleeve 25. rllhe spring 26 constantly acts on the collar 27 toyieldingly maintain the end 18 of thevalve member on its seat 19 tocutof the flow of liquid fuel. The outer end of the valve member 17 hasconnected thereto a Wire 28 which leads to a convenient point on thedashboard so that the operator of the vehicle may retract the valvemember 27 for priming the engine by allowing liquid fuel to pass out ofthe inlet 14 while the choke 15 is in a closed position.

Suitable operating means is provided for simultaneously operating thevalve member 17 and the choke valve 15. Thesaid operati ing means, inthe present instance includes a bell crank lever 29, the arm 30 of whichhas connected thereto a rod or thelike 31 leading v to a controldevicesuch as the foot accelerator, and the arm 32 of said lever 29 isconnectedV to an arm 33 on one end of the shaft 16 by an adjustableelement 34. The arm 33 has connected to one end thereof a member 35 byscrew bolts 36, which extend respectively in slots 37 in the arm 33. Themember 35 is formed with an extension in the form of an arcuate andtapered portion or cam 38. The said cam 38 is adapted to coact'with oneend of the block or nut 21 on the stem of the valve member 17 inresponse to the movement of the lever 29 to either move the end 18 0E ofits seat 19, or to allow the spring 26 to function to bring the end 18on the seat 19. By providing the bolts 36 and slots 37 the cam 38 may beadjusted so as to vary the extent of movement of the valve member 17.The nut 21 may also be adjusted to vary the action of the spring 26.Thus provision is made for obtaining a proper working condition of partsof the device which control the supply of liquid fuel. As the lever 29is moved in one direction to retract the valve member 17, the chokevalve 15 will be moved at the same time to openedposition. Air will thenbe permitted to enter the mixing chamber 13 through the inlet l2 to bemixed with the liquid fuel sucked from the inlet 14, and as aconsequence, a full and rich mixture of gas will be passing to theintake manifold of the engine. When the lever 29 is moved bymanipulating the rod 31 to move the choke valve 15 to a closed position,the cam 38 will be moved to a position so that the spring 26 canfunction to move the end 18 of the valve member 17 to a partlyopenedposition, with -respect to the seat 19, to allow a small amount ofliquid fuel to be sucked in by the engine for the purpose of priming theengine.

Means is provided for controlling the operation of the means whichserves to operate the choke valve and the valve controlling the The.said control means, in the present instance, consists of a member 39secured to the casing 10 in any suitable manner and the said member 39is formed to provide a stop 40, which isl in fact` a first fixed stop,

and a stop 41, which is in fact. a second fixed stop. and there isprovided a movable stop 42 which is adapted to coact with the stops 40and 41. The stop 42 is carried by the arm 33 and has a nut^43 at oneend, a head 44 at the opposite end between which and the arm 33 isarranged a spring 45. A flexible element in the form of a wire 46. isconnected to the end of the stop 42 having the nut 43..thereon. The nut43 serves for adjusting the stop 42 to vary its longitudinal movement inone direction. The spring. 45 has a normal tendency to yieldably holdthe stop 42 in a normal j extended position so that as the arm 33 ismoved clockwise, the head 44 will engage the stop 40. The choke valve isin a closed position and the valve member 17 is in a partly openedposition when the stop 42 engages the 'stop 40. By retracting the stop42 by pulling on the wire 46, the arm 33 may be moved to such a positionas to move the choke valve 15 to an open position, while allowing thevalve member 17 to be moved to a closed position. Under this arrangementliquid fuel will be prevented from entering the mixing chamber, and airwill be allowed to pass through the inlet 12 to be sucked into theengine cylinders, and this without creating a vacuum which results inoil being drawn into the cylinders from the crank case which ultimatelycauses carbon to exist in the cylinders. The engine then operates likean air compressor and therefore acts as a brake for the automobile. Whenthe arm 23 is retractedin a counter-clockwise direction to its extremelimit of movement in that direction, the choke valve 15 will be in anopened positiony while the valve 17 will be fully retracted to allow thefull charge of both liquid fuel and air to pass into the mixing chamber,to be there thoroughly mixed prior to its being sucked, in the form ofgas, into the intake manifold.

In order to provide a satisfactory mixture or gas for the engine whileidling, there is provided in' the wall of the casing 10 an air port 47which is controlled by an element 48 in the form of screw, one end ofwhich is movable into and out of the port 47, the latter being incommunication with ducts 49 through which airvpasses to the port intothe mixing chamber 13. When the valve 15 is in a closed position, thevalve member 17 will be in a. partly opened position, and the air suckedin through the port 47 will mix with fuel passing out of the inlet 14thereby producing a satisfactory fuel mixture for keeping the enginerunning idle.

I claim:

1. In a carburetor, a casing forming an air inlet and a mixing chamber,a choke valve controlling said air inlet, 'a liquid fuel inlet betweenthe air inlet and the mixing chamber, a valve. controlling said liquidfuel inlet, said valve including a valve member, a seat with which saidvalve member coacts; an adjustable nut on'said valve member, a camsupporte-d for movement to coact with said nut, means for effecting themovement of the cam in one direction to move the valve member off of itsseat, means constantly acting on said valve-member to move it to closedposition on its seat and to yieldably hold the valve member on its seat,and means connected directly with said valve member to move it off ofits seat.

y 2. In a carburetor, a casing forming an air inlet and a mixingchamber, a chokevalve controlling said air inlet, a liquid `fuel inlet.between the air inlet and the mixing chamber, a valve controlling saidliquid fuel inlet, said valve including a valve member, and a seat withwhich said valve member coacts;

jan adjustable nut on said valvemember, a

cam supported for movement to coact with said nut, operating means foreiecting the movement of the cam in one direction to move 'the valvemember oli' of its seat, and

i means constantly acting on said valve mem-

